81134199936 has 512 divisors, whose sum is σ = 255688704000. Its totient is φ = 25291284480.

The previous prime is 81134199919. The next prime is 81134200001. The reversal of 81134199936 is 63999143118.

It is a Harshad number since it is a multiple of its sum of digits (54).

It is a nude number because it is divisible by every one of its digits.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 638851905 + ... + 638852031.

It is an arithmetic number, because the mean of its divisors is an integer number (499392000).

Almost surely, 2^81134199936 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 81134199936, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (127844352000).

81134199936 is an abundant number, since it is smaller than the sum of its proper divisors (174554504064).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

81134199936 is a wasteful number, since it uses less digits than its factorization.

81134199936 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 337 (or 319 counting only the distinct ones).

The product of its digits is 1259712, while the sum is 54.

The spelling of 81134199936 in words is "eighty-one billion, one hundred thirty-four million, one hundred ninety-nine thousand, nine hundred thirty-six".